I haven't switched or started dual-booting yet because I haven't had time, but I've read the recommendation that the best way to do dual or even multiple boot is to have separate physical OS drives and select which one to boot from with the BIOS boot selector. Smaller SSD drives are pretty cheap these days, especially if you get them used on ebay or whatever. I picked up a Samsung 240 with 0% wearout for like $20 bucks.